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Anorectal function in the solitary rectal ulcer syndrome   总被引:8,自引:6,他引:2  
The anorectal function of nine patients with solitary rectal ulcer syndrome (SRUS) (5 F: 4 M, median age, 27 (range, 19–41 years) and nine control subjects (5 F: 4 M, median age, 47 (35–66)P<0.01) has been investigated by a new technique that radiologically visualizes the anorectum during voiding of a semisolid contrast medium, while simultaneously measuring intrarectal pressure and anal sphincter EMG activity. A degree of rectal prolapse was demonstrated in eight of the SRUS patients; six of these lesions were clinically occult. Abnormal failure of the anal sphincter to relax on voiding was present in seven of the SRUS patients. These abnormalities resulted in the SRUS patients requiring a greater increase in intrarectal pressure (median, 100 cm water) to void than the control subjects (median, 65 cm water,P<0.01). This combination of high intrarectal pressure and rectal prolapse during straining seems to be the cause of SRUS This work was supported by a grant from the Medical Research Council.  相似文献   
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Paediatric dacryocystorhinostomy   总被引:1,自引:0,他引:1  
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease.  相似文献   
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A second-generation 5000 rad radiation hybrid (RH) map of the cattle genome was constructed primarily using cattle ESTs that were targeted to gaps in the existing cattle-human comparative map, as well as to sparsely populated map intervals. A total of 870 targeted markers were added, bringing the number of markers mapped on the RH(5000) panel to 1913. Of these, 1463 have significant BLASTN hits (E < e(-5)) against the human genome sequence. A cattle-human comparative map was created using human genome sequence coordinates of the paired orthologs. One-hundred and ninety-five conserved segments (defined by two or more genes) were identified between the cattle and human genomes, of which 31 are newly discovered and 34 were extended singletons on the first-generation map. The new map represents an improvement of 20% genome-wide comparative coverage compared with the first-generation map. Analysis of gene content within human genome regions where there are gaps in the comparative map revealed gaps with both significantly greater and significantly lower gene content. The new, more detailed cattle-human comparative map provides an improved resource for the analysis of mammalian chromosome evolution, the identification of candidate genes for economically important traits, and for proper alignment of sequence contigs on cattle chromosomes.  相似文献   
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OBJECTIVE: To evaluate human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR) sequence diversity among distinct populations within India and to determine the prevalent subtype. STUDY DESIGN/METHODS: Analysis of the 3'LTR was conducted from 28 HIV-1-positive samples: 1992-1993 (Pune, New Delhi) and 1995-1996 (Pune, Mumbai and Vellore). Genomic DNA was extracted from cocultivated peripheral blood mononuclear cells (PBMCs) and used for polymerase chain reaction (PCR) amplification and sequencing using dye terminator chemistry. Sequences were edited, aligned, and analyzed phylogenetically utilizing gap-stripped and bootstrapping parameters. Mobility shift assays were used to confirm binding activity. RESULTS: All nucleotide sequences were HWV-1 subtype C based on phylogenetic analysis. The isolates from Pune/Delhi formed subclusters when analyzed separately, irrespective of time or sample source. However, no significant subclustering was observed with isolates from Mumbai or Vellore or with the entire sample set when analyzed collectively. Subtype-specific enhancer analysis revealed an expected third NF-kappaB site but also revealed six isolates with insertions and deletions not previously described, one of which resembles an AP-1 binding site. CONCLUSIONS: The results confirm the prevalence of HIV-1C and suggest increasingly complex phylogeny of HIV-1C within India, such that the previously observed subclustering may no longer adequately reflect the diversity of isolates currently circulating throughout India.  相似文献   
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An ordered comparative map of the cattle and human genomes   总被引:14,自引:2,他引:14       下载免费PDF全文
A cattle-human whole-genome comparative map was constructed using parallel radiation hybrid (RH) mapping in conjunction with EST sequencing, database mining for unmapped cattle genes, and a predictive bioinformatics approach (COMPASS) for targeting specific homologous regions. A total of 768 genes were placed on the RH map in addition to 319 microsatellites used as anchor markers. Of these, 638 had human orthologs with mapping data, thus permitting construction of an ordered comparative map. The large number of ordered loci revealed > or =105 conserved segments between the two genomes. The comparative map suggests that 41 translocation events, a minimum of 54 internal rearrangements, and repositioning of all but one centromere can account for the observed organizations of the cattle and human genomes. In addition, the COMPASS in silico mapping tool was shown to be 95% accurate in its ability to predict cattle chromosome location from random sequence data, demonstrating this tool to be valuable for efficient targeting of specific regions for detailed mapping. The comparative map generated will be a cornerstone for elucidating mammalian chromosome phylogeny and the identification of genes of agricultural importance."Ought we, for instance, to begin by discussing each separate species-in virtue of some common element of their nature, and proceed from this as a basis for the consideration of them separately?" from Aristotle, On the Parts of Animals, 350 B.C.E.  相似文献   
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Histopathological assessment and flow cytometric analyses were carried out on 32 placentas (representative of each trimester) and 88 molar pregnancies. Three first trimester placentas were triploid, and the remaining 29 placentas were diploid. Of the 88 cases originally diagnosed as molar pregnancies, 26 were triploid (two complete moles, 20 partial moles, and four hydropic abortions); 59 were diploid (46 complete moles, 10 partial moles, three hydropic abortions); one was tetraploid (partial mole); and two were DNA aneuploid (one partial mole, one complete mole). A significantly increased hyperdiploid fraction (a measure of cell proliferation) was detected in diploid complete moles (p less than 0.0001) and cases of persistent trophoblastic disease (p less than 0.001) when compared with diploid placentas and diploid partial moles. All seven cases of established persistent trophoblastic disease, for which follow up was available, were diploid and showed high hyperdiploid fractions within the range for diploid complete moles. These findings suggest that flow cytometric DNA measurements may be an important aid in the diagnosis of molar pregnancy. The high degree of cell proliferation found in this study may explain the premalignant potential of complete hydatidiform moles.  相似文献   
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恶性肿瘤患者血清与尿液中一氧化氮含量测定   总被引:1,自引:1,他引:0  
0 引言一氧化氮(Nitric oxide,NO)是一种具有活跃生物化学性质的无机小分子. NO对许多肿瘤细胞和微生物有细胞毒性[1],为探讨NO与肿瘤的关系,我们检测了119例恶性肿瘤患者血清及尿液中的NO.  相似文献   
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